23.2 Lifetimes: Functions | mut_one() appears to just work?

[nelsonjchen]

If I uncomment mut_one(), it looks like it just works and it doesn't error out. Did something change recently?

impl Triplet {
    // First attempt: No explicit lifetimes
    // Error! The compiler needs information about the lifetimes
    fn mut_one(&mut self) -> &mut int {
        &mut self.one
    }
   // ...
}

[nelsonjchen]

http://rustbyexample.com/lifetime/fn.html

[mirkonasato]

Just noticed the same: if you uncomment mut_one() and call it from main() everything works fine using the latest master or 0.12.0. You do get an error with 0.11.0.

[kosciej]

I believe that recently lifetime elision was implemented in Rust.
This is the RFC which suggests some of the lifetime annotations unnecessary:
rust-lang/rfcs#141
https://github.com/rust-lang/rfcs/blob/091e5fabbbbd0419b8d291a6d1cd8e6e59c56deb/text/0141-lifetime-elision.md

[abonander]

Related to #195

[steveklabnik]

This has since been fixed.